JP2011083127A - Grommet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a grommet from deforming to cause flooding during high pressure vehicle washing. <P>SOLUTION: In the grommet molded of rubber or elastomer and attached to a wire harness which is routed in a vehicle for fitting in the through-hole of a body panel, an enlarged cylindrical part 3 is continuous to one end of a small diameter cylindrical part 2, a thick large diameter part 4 is provided at the tip of the enlarged cylindrical part on the large diameter side, an annular recess 5 locked with the body is provided between the thick large diameter part and the enlarged cylindrical part, the enlarged cylindrical part on the side of the small diameter cylindrical part consists of a double wall, i.e., an inner wall 10 continuous to the small diameter cylindrical part and an outer wall 11 spaced apart from the inner wall by an air gap, the side provided with the recess locked with the body consists of an integral part 13 where the inner wall and the outer wall are continuous, and annular slits 14a and 14b are provided in the integral part 13 and the outer wall. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a grommet that is attached to a wire harness that is routed to an automobile and is attached to a through hole of a vehicle body panel.In particular, when the grommet attached to the vehicle body panel is subjected to a large load from the outside, It is intended not to come off.

  Conventionally, when it is necessary to route a wire harness routed to an automobile through a vehicle body panel, a grommet made of rubber or elastomer is externally attached to the wire harness and attached, and the grommet is attached to a through hole formed in the vehicle body panel. It is installed to ensure waterproofing, dustproofing, and sound insulation in the passenger compartment.

The grommet is attached to, for example, a wire harness routed in the lower part of the floor, and is attached to a through hole provided in the floor panel. In this way, when the grommet is exposed and attached to the lower surface of the floor panel, the automobile may be pulled up at the time of high-pressure washing and the high-pressure washing water may be sprayed from below the floor in this case. May be deformed and may be displaced from or disengaged from the through hole of the floor panel.
In some cases, grommets are also attached to a wire harness that extends between the vehicle body panel and the side door, and both ends of the grommets are attached to through holes in the vehicle body panel or the door panel. Also in this case, the grommet is exposed between the vehicle body panel and the door panel, and even when the grommet is inadvertently touched and pushed by a worker on the vehicle line, the grommet may be deformed to be displaced from the through hole or detached. .

Conventionally, Japanese Patent Application Laid-Open No. 2006-223075 has proposed a grommet shown in FIG. 9 with improved waterproofness during high-pressure cleaning.
In the grommet, a seal projection 103 that presses against the vehicle body panel P is provided on the large-diameter annular panel fitting portion 102 at the distal end on the large-diameter side of the enlarged-diameter cylindrical portion 101, and a seal protection wall 104 is provided on the outer periphery of the seal projection 103. It is protruding. A gap is secured between the front end of the seal protection wall 104 and the vehicle body panel P.
It is described that the provision of the seal protection wall 104 reduces the influence of high-pressure water directly on the seal protrusion 103 by receiving the injection water at the seal protection wall 104 against strong jet water from the outside. Yes.

JP 2006-223075 A

In the grommet for high pressure car wash shown in FIG. 9, a seal protection wall 104 is provided on the outer periphery of the seal projection 103. However, as shown in FIG. 10, the large-diameter annular panel fitting portion 102 is located on the inner side of the vehicle. The large-diameter cylindrical portion 101 is located outside the vehicle, and the high-pressure washing water at the time of high-pressure washing is often injected into the large-diameter cylindrical portion 101 that is easily bent.
In this case, when the diameter-expanded cylindrical portion 101 is bent inward by the high-pressure washing water, the peripheral wall 106 of the vehicle body locking groove that fits to the periphery of the through hole H of the vehicle body panel P is pulled in a direction away from the vehicle body panel P. It is done. As a result, a gap is generated between the sealing surface of the peripheral wall 106 that presses against the vehicle body panel P and the vehicle body panel P, and high-pressure cleaning water may enter the vehicle interior through the through hole.

  The above-mentioned grommet problem also occurs in the grommet between the vehicle body panel and the back door or side door other than during high-pressure car washing. That is, it also occurs when the grommet is exposed when the door is opened, an occupant or a baggage hits the enlarged diameter cylindrical portion of the grommet, and the enlarged diameter cylindrical portion is pressed inward.

  The present invention has been made in view of the above problems, and when a load is applied to the grommet at the time of high-pressure car washing or the like, when the diameter-enlarged cylindrical portion of the grommet is deformed, a seal surface closely attached to the periphery of the through hole of the vehicle body panel is provided. The problem is to prevent deformation and prevent flooding.

In order to solve the above problems, the present invention provides:
A grommet molded from rubber or elastomer that is attached to a wire harness routed in an automobile and fitted in a through hole of a vehicle body panel,
An enlarged tube portion is continuous with one end of the small-diameter tube portion, and a thick-walled large-diameter portion is provided at the large-diameter end of the expanded-diameter tube portion. Vehicle body locking recesses are provided, and
The small-diameter cylindrical portion side of the large-diameter cylindrical portion is a double wall composed of an inner wall portion that is continuous with the small-diameter cylindrical portion and an outer wall portion that is provided with a gap between the inner wall portion and a vehicle body locking recess. The other side is an integral part in which the inner wall part and the outer wall part are continuous,
A grommet is provided in which an annular slit is provided in the integral part and the outer wall part.

  As described above, the grommet of the present invention has a double wall structure of the inner wall portion and the outer wall portion on the small diameter side of the large diameter cylindrical portion that is continuous with the small diameter cylindrical portion. The outer wall portion is dented to the inner wall portion side and deformed, and slits provided on the outer peripheral surface of the outer wall portion and the outer peripheral surface of the integral portion on the large-diameter side are opened according to the deformation of the outer wall portion. In such a manner, it is deformed and stretched to follow the deformation. Therefore, the bottom surface of the vehicle body locking recess that is pressed against the periphery of the through hole of the vehicle body panel without exerting a tensile load corresponding to the deformation of the outer wall portion on the bottom surface of the vehicle body locking recess provided on the outer diameter end side of the enlarged diameter cylindrical portion. Can be prevented from floating from the body panel and creating a gap. Thereby, it is possible to reliably prevent the high-pressure washing water from entering the vehicle interior through the gap between the through hole and the grommet.

It is preferable that the number of the slits provided on the outer peripheral surface of the integrated portion is three or more and provided at a small pitch, while the number of the slits provided on the outer wall portion is one or two at a large pitch.
In this way, the integral part continuous to the bottom surface of the vehicle body locking recess that is in pressure contact with the vehicle body panel and serves as a sealing surface is provided with a small number of slits at a small pitch of about 3 to 5, so that the outer wall When the portion is deformed by water pressure, the outer peripheral surface of the integral portion can be extended to more reliably prevent a tensile load from being applied to the bottom surface serving as the sealing surface.
On the other hand, since the outer wall portion is deformed by water pressure and is thin, it is preferable that the number of slits provided on the outer peripheral surface is approximately one or two from the viewpoint of maintaining strength. Note that an acute-angle V-groove may be used instead of the slit.
The slit is preferably cut to a depth of about half the wall thickness.

It is preferable that an annular V-shaped groove is provided on the inner peripheral surface of the integrated part, and the V-shaped groove is provided in a staggered arrangement with slits on the outer peripheral surface of the integrated part.
As described above, when the V-shaped groove is provided also on the inner peripheral surface of the integral part, the inner peripheral side can be deformed so that the outer peripheral side is contracted when the outer peripheral side is extended, and the tensile load on the seal surface is further prevented. it can. And the slit of the outer peripheral surface provided in an integrated part and the V-shaped groove | channel of an internal peripheral surface can carry out staggered arrangement | positioning, and can hold | maintain the intensity | strength of an integrated part. Note that when the water pressure directly hits the enlarged diameter cylindrical portion, the impact is absorbed by the deformation of the outer wall portion and the inner wall portion is not deformed. Therefore, no V-shaped groove is provided in the inner wall portion.
A slit similar to the outer peripheral surface may be provided instead of the V-shaped groove on the inner peripheral surface.

  The outer peripheral surface of the small-diameter cylindrical portion is fixed by winding an adhesive tape around the outer peripheral surface of the wire harness through which the small-diameter cylindrical portion is inserted, and provided at the tips of the inner wall portion and the outer wall portion of the enlarged-diameter cylindrical portion. Is preferably in an open state.

As described above, when the inner wall portion of the enlarged diameter cylindrical portion and the outer wall portion having a gap are left in an open state, the outer wall portion that has been directly hit by water pressure is easily deformed.
The outer wall portion may also be wrapped with an adhesive tape to close the opening to provide a sealed space between the outer wall portion and the inner wall portion, and the space may be used as a sound insulation space. Also in this case, since the slit is provided in the outer wall portion and the integral portion, the slit can be opened and follow the deformation when the outer wall portion is deformed by water pressure.

The grommet of the present invention is attached to a wire harness routed at the lower part of the floor panel, and is attached to the through hole of the floor panel so that the expanded cylindrical portion is exposed to the lower part of the floor panel in the attached state. It is most preferably used when mounting.
In addition, the present invention can also be applied to a case where it is externally mounted on a wire harness that extends between the vehicle body and the side door and is attached to the through holes of the vehicle body panel and the door panel.

  The grommet of the present invention described above absorbs an impact by deforming the outer wall portion of the enlarged diameter cylindrical portion when the high pressure washing water is injected into the enlarged diameter cylindrical portion and the water pressure hits directly during high-pressure washing of the automobile. Since the slit is opened and extended according to the deformation, no load is applied to the seal surface in contact with the vehicle body panel, the seal surface is prevented from floating, and the occurrence of water intrusion into the passenger compartment can be prevented.

It is the schematic which shows the state which attached the grommet of 1st embodiment of this invention to the through-hole of the floor panel. It is a front view of the grommet of a first embodiment. (A) is a cross-sectional perspective view of the grommet, and (B) is an enlarged view of a main part. It is a perspective view in the state where a wire harness was attached to the grommet. It is sectional drawing which shows the state which attached the said grommet to the floor panel. It is sectional drawing which shows the state which received the direct impact of water pressure at the time of a car wash, and the grommet deform | transformed. It is sectional drawing which shows 2nd embodiment. (A) (B) is drawing which shows 3rd embodiment. It is drawing which shows a prior art example. It is drawing which shows another prior art example.

Hereinafter, embodiments of the grommet of the present invention will be described with reference to the drawings.
1 to 6 show a grommet 1 according to the first embodiment.
As shown in FIG. 1, the grommet 1 is attached to a wire harness W / H routed along the lower surface of the vehicle body panel P made of a floor panel, and is inserted into a through hole H formed in the vehicle body panel P from below. Attached.

  The grommet 1 is formed of rubber or elastomer, and has a small-diameter cylindrical portion 2 through which the wire group W constituting the wire harness W / H is brought into close contact with each other, and an enlarged diameter that continuously expands at one end of the small-diameter cylindrical portion 2. A ring-shaped thick-walled large-diameter portion 4 provided at the periphery of the large-diameter side opening of the large-diameter tube portion 3, and a ring-shaped outer peripheral surface of the thick-walled large-diameter portion 4 and the large-diameter tube portion 3. And a vehicle body locking recess 5 provided continuously. The vehicle body locking recess 5 includes a side surface 5a on the enlarged diameter cylindrical portion side, a side surface 5b on the thick large diameter portion side, and a bottom surface 5c sandwiched between both side surfaces 5a and 5b. The periphery of the through hole H of the vehicle body panel P is inserted and locked in the vehicle body locking recess 5, and the bottom surface 5 c becomes a seal surface that presses against the inner peripheral surface of the through hole H in this state.

  As shown in FIG. 3, the enlarged-diameter cylindrical portion 3 has a double-wall structure, and an inner wall portion 10 that is continuous with one end of the small-diameter cylindrical portion 2 and a large-diameter side portion of the inner wall portion 10. The outer wall portion 11 is disposed so as to cover the outer circumferential surface with a gap C therebetween. That is, the continuous side with the small diameter cylindrical portion 2 is constituted by the thin inner wall portion 10 and the outer wall portion 11, and an opening 12 between the inner wall portion 10 and the outer wall portion 11 exists at the small diameter end. On the other hand, an annular integral part 13 in which the inner wall part 10 and the outer wall part 11 are connected is provided on the thick large diameter part 4 side.

Since the diameter-enlarging cylindrical portion 3 needs to be deformed by bending inward when the grommet 1 is passed through the through hole H of the panel, both the inner wall portion 10 and the outer wall portion 11 are relatively thin and easily bent. In addition, the thickness of the integral part 13 is about half that of the thick large-diameter part 4.
The length L1 of the inclined portion having a double wall structure composed of the inner wall portion 10 and the outer wall portion 11 is about ½ of the total length of the inclined portion of the diameter-expanded cylindrical portion 3.

  A plurality of annular slits 14a (four in this embodiment) are provided on the outer peripheral surface of the large-diameter side integral portion 13 of the enlarged diameter cylindrical portion 3 at intervals, and the outer wall is continuous with the integral portion 13 The part 11 is also provided with an annular slit 14b. The pitch between the slits 14a is relatively dense. The number of slits 14b is one or a plurality of about two to three. In the case of a plurality of slits 14b, the pitch between the slits 14b is larger than the pitch between the slits 14a, and the pitch is gradually increased toward the smaller diameter side. Yes.

  In addition, annular V-shaped grooves 15 are also provided on the inner peripheral surface of the large-diameter integrated portion 13, and the V-shaped grooves 15 are alternately provided with the slits 14 a on the outer peripheral side being displaced. The inner wall portion 10 is not provided with a V-shaped groove.

  As shown in FIG. 4, the wire harness W / H is attached to the grommet 1 having the above-described configuration. As shown in FIG. 4, the small diameter cylindrical portion 2 is expanded and the electric wire group W is passed through. The end portion of the small-diameter cylindrical portion 2 and the wire group W are fixedly wound around the adhesive tape T. Therefore, in the enlarged diameter cylindrical portion 3, the opening 12 between the inner wall portion 10 and the outer wall portion 11 remains open, and the gap C is continuous with the opening 12 to make the outer wall portion 11 easily bent.

  As shown in FIG. 5, the wire harness to which the grommet 1 is attached is inserted into the through-hole H of the vehicle body panel P composed of a floor panel from the small diameter cylindrical portion 2 side, and the enlarged diameter cylindrical portion 3 is deformed inward. Through the through-hole H, the periphery of the through-hole H is inserted and locked into the vehicle body locking recess 5. In this state, both sides of the vehicle body panel are sandwiched between both side surfaces 5a and 5b of the vehicle body locking recess 5, the inner peripheral surface of the through hole H is in pressure contact with the bottom surface 5c of the vehicle body locking recess 5, and the bottom surface 5c is the sealing surface. It becomes. The enlarged diameter cylindrical portion 3 and the small diameter cylindrical portion 2 of the grommet 1 protrude downward from the floor panel and are exposed to the outside.

  When an automobile is subjected to high-pressure washing, the automobile may be lifted by a lift in other countries or the like, and high-pressure washing water may be sprayed toward the automobile floor. In that case, the diameter expansion cylinder part 3 of the grommet 1 exposed outside from the floor panel receives a direct hit of water pressure, and deforms as shown in FIG. The deformation occurs in the outer wall portion 11 that is easily bent with a gap C with respect to the inner wall portion 10, the outer wall portion 11 is bent inward, and the inner wall portion 10 is hardly deformed.

  As described above, when the outer wall portion 11 is bent and deformed inward, the slit 14b is provided on the outer wall portion 11 and the slit 14a is provided on the outer peripheral surface of the continuous integral portion 13. Therefore, the slits 14a and 14b are provided. Is deformed in the opening direction and gives an extension to the outer peripheral side of the enlarged diameter cylindrical portion 3. Further, the V-shaped groove 15 on the inner peripheral side of the integrated portion 13 is deformed in the contracting direction in accordance with the expansion on the outer peripheral side. Thereby, it is possible to prevent a tensile load due to the deformation of the enlarged diameter cylindrical portion 3 from being applied to the bottom surface 5c of the vehicle body locking recess 5 provided at the front end of the integral portion 13 on the large diameter side. Therefore, it is possible to prevent the bottom surface 5c from floating from the vehicle body panel P, and to maintain a state in which the bottom surface 5c is pressed against the vehicle body panel P, and no gap is generated. As a result, it is possible to reliably prevent water from entering the vehicle interior through the grommet 1 and the through hole H during high-pressure cleaning.

Note that the adhesive tape T for fixing the grommet 1 to the wire harness W / H may be wound around the distal end of the outer wall portion 11 of the enlarged diameter cylindrical portion 3 to close the opening 12.
With this configuration, the gap C between the outer wall portion 11 and the inner wall portion 10 can be used as a sealed sound insulation space. Also in this case, since the slits 14a and 14b are provided on the outer peripheral surfaces of the outer wall portion 11 and the integral portion 13, the outer wall portion 11 can be easily deformed inward when subjected to direct water pressure.

FIG. 7 shows a grommet 1A according to the second embodiment.
The grommet 1A is different from the grommet 1 of the first embodiment in that the slit 14a is provided only in the outer peripheral portion of the integral portion 13 and the slit is not provided in the inner peripheral surface and the outer wall portion 11.
Since other configurations are the same, the same reference numerals are given and description thereof is omitted.

  As described above, even if the slit 14a is provided on the outer peripheral side without providing the V-shaped groove on the inner peripheral side of the integrated portion 13, the slit 14a is deformed inward when the outer wall portion 11 is directly hit by water pressure. Is opened to follow the deformation, and a tensile load is not applied to the bottom surface 5c of the vehicle body locking recess 5, and it is possible to prevent the bottom surface 5c from being deformed from the vehicle body panel P and generating a gap.

8A and 8B show a grommet 1B according to the third embodiment.
The grommet 1B is a grommet that is attached to a wire harness that is bridged between the side door 20 and the vehicle body panel P.
The grommet 1B includes vehicle body locking portions 23A and 23B at both ends of the bellows tube portion 22, and both ends of the bellows tube portion 22 have the same configuration as in the first embodiment, and the small diameter tube portion 2, the large diameter tube portion 3, A thick large-diameter portion 4 and a vehicle body locking recess 5 are provided. In addition, the enlarged diameter cylindrical portion 3 is provided with the inner wall portion 10, the double wall portion of the outer wall portion 11 and the integral portion 13, and the outer peripheral surface of the outer wall portion 11 and the outer peripheral surface of the integral portion 13 are provided with slits 14 a.

  As shown in FIG. 8 (B), the wire harness W / H is attached to the grommet 1B, and the vehicle body locking recesses 5 at both ends are fitted to the vehicle body panel P and the door panel DP. It is attached to. In the grommet 1B attached in this way, the enlarged diameter cylindrical portions 3 and 3 continuing to both ends of the bellows cylindrical portion 22 are exposed when the door is opened. In this state, when an operator of the vehicle line inadvertently negotiates with the enlarged diameter cylindrical portion 3 of the grommet 1B and causes the enlarged diameter cylindrical portion 3 to be deformed, as described in the first embodiment, the expansion is performed. The diameter cylinder part 3 expand | extends according to a deformation | transformation, and can deform | transform the bottom face 5c press-contacted to the vehicle body panel P or the door panel DP.

  The third embodiment is a grommet attached between the vehicle body and the back door, but can also be applied to a grommet attached between the vehicle body and the side door.

DESCRIPTION OF SYMBOLS 1 Grommet 2 Small diameter cylinder part 3 Wide diameter cylinder part 4 Thick large diameter part 5 Car body latching recessed part 5a, 5b Side surface 5c Bottom 10 Inner wall part 11 Outer wall part 12 Opening 13 Integrated part 14a, 14b Slit 15 V-shaped groove C Cavity W Wire group W / H Wire harness T Adhesive tape P Body panel H Through hole

Claims (5)

A grommet molded from rubber or elastomer that is attached to a wire harness routed in an automobile and fitted in a through hole of a vehicle body panel,
An enlarged tube portion is continuous with one end of the small-diameter tube portion, and a thick-walled large-diameter portion is provided at the large-diameter end of the expanded-diameter tube portion. Vehicle body locking recesses are provided, and
The small-diameter cylindrical portion side of the large-diameter cylindrical portion is a double wall composed of an inner wall portion that is continuous with the small-diameter cylindrical portion and an outer wall portion that is provided with a gap between the inner wall portion and a vehicle body locking recess. The other side is an integral part in which the inner wall part and the outer wall part are continuous,
An annular slit is provided in the integral part and the outer wall part, The grommet characterized by the above-mentioned.   The number of the slits provided in the outer wall portion is one or two at a large pitch, while the slits on the outer peripheral surface of the integrated portion are provided at a small pitch as three or more. Grommet.   The annular V-shaped groove or slit is provided on the inner peripheral surface of the integral part, and the V-shaped groove or slit is provided in a staggered arrangement with the slit on the outer peripheral surface of the integral part. Grommet.   The outer peripheral surface of the small-diameter cylindrical portion is fixed by winding an adhesive tape around the outer peripheral surface of the wire harness through which the small-diameter cylindrical portion is inserted, and provided at the tips of the inner wall portion and the outer wall portion of the enlarged-diameter cylindrical portion. The grommet according to any one of claims 1 to 3, wherein the grommet is in an open state.   5. The wire harness routed in a lower portion of the floor panel is attached to a through hole of the floor panel, and the expanded cylindrical portion is exposed to the lower portion of the floor panel in the attached state. The grommet of any one of Claims.

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